Hypomyelination and Congenital Cataract: Clinical, Imaging, and Genetic Findings in Three Tunisian Families and Literature Review

Ichraf Kraoua; Yosra Bouyacoub; Cyrine Drissi; Mariem Chargui; Ibtihel Rebai; Ahmed Chebil; Hédia Klaa; Hanene Benrhouma; Aida Hassen; Neziha Gouider-Khouja; Sonia Abdelhak; Odile Boespflug-Tanguy; Ilhem Ben Youssef-Turki; Imen Dorboz

doi:10.1055/s-0041-1728654

Neuropediatrics, Table of Contents

Neuropediatrics 2021; 52(04): 302-309
DOI: 10.1055/s-0041-1728654

Original Article

Hypomyelination and Congenital Cataract: Clinical, Imaging, and Genetic Findings in Three Tunisian Families and Literature Review

Ichraf Kraoua^*

¹LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, Tunisia

,

Yosra Bouyacoub‡^*

²LR11IPT05, Laboratory of Biomedical Genomics and Oncogenetics, Pasteur Institute of Tunis, University of Tunis El Manar, Tunis, Tunisia

,

Cyrine Drissi‡^*

³Department of Neuroradiology, National Institute Mongi Ben Hmida of Neurology, Tunis, Tunisia

,

Mariem Chargui

²LR11IPT05, Laboratory of Biomedical Genomics and Oncogenetics, Pasteur Institute of Tunis, University of Tunis El Manar, Tunis, Tunisia

,

Ibtihel Rebai

¹LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, Tunisia

,

Ahmed Chebil

⁴Department B of Ophthalmology, Hedi Rais Institute of Ophthalmology, Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis, Tunisia

,

Hédia Klaa

¹LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, Tunisia

,

Hanene Benrhouma

¹LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, Tunisia

,

Aida Hassen

¹LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, Tunisia

,

Neziha Gouider-Khouja

¹LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, Tunisia

,

Sonia Abdelhak

²LR11IPT05, Laboratory of Biomedical Genomics and Oncogenetics, Pasteur Institute of Tunis, University of Tunis El Manar, Tunis, Tunisia

,

Odile Boespflug-Tanguy

⁵Université de Paris, NeuroDiderot, UMR 1141, INSERM, Neuropédiatrie, LEUKOFRANCE, APHP, Hôpital Robert Debré, France

,

Ilhem Ben Youssef-Turki

¹LR18SP04, Department of Child and Adolescent Neurology, National Institute Mongi Ben Hmida of Neurology, University of Tunis El Manar, Tunis, Tunisia

,

Imen Dorboz

⁵Université de Paris, NeuroDiderot, UMR 1141, INSERM, Neuropédiatrie, LEUKOFRANCE, APHP, Hôpital Robert Debré, France

› Author Affiliations

Abstract

Hypomyelination and congenital cataract (HCC) is characterized by congenital cataract, progressive neurologic impairment, and diffuse myelin deficiency. This autosomal recessive disorder is caused by homozygous variant in the FAM126A gene. Five consanguineous Tunisian patients, belonging to three unrelated families, underwent routine blood tests, electroneuromyography, and magnetic resonance imaging of the brain. The direct sequencing of FAM126A exons was performed for the patients and their relatives. We summarized the 30 previously published HCC cases. All of our patients were carriers of a previously reported c.414 + 1G > T (IVS5 + 1G > T) variant, but the clinical spectrum was variable. Despite the absence of a phenotype–genotype correlation in HCC disease, screening of this splice site variant should be performed in family members at risk.

Keywords

hypomyelination - cataract - HCC - FAM126A gene - MRI

Full Text

References

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